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Version:

$ openshift-install version
openshift-install 4.10.6
built from commit 17c2fe7527e96e250e442a15727f7558b2fb8899
release image quay.io/openshift-release-dev/ocp-release@sha256:88b394e633e09dc23aa1f1a61ededd8e52478edf34b51a7dbbb21d9abde2511a
release architecture amd64

Platform:

aws

Please specify:
* IPI

What happened?

When attempting to install a cluster with an installConfig.yaml with:

    metadata:
      name: "shared-410"
    baseDomain: "openshift.redhatworkshops.io"

It finds the DNS record "bastion-shared-410.openshift.redhatworkshops.io" and fails with an error:

   "Platform Provisioning Check": <nil>: Invalid value: "": the zone already has record sets for the domain of the cluster: [bastion-shared-410.openshift.redhatworkshops.io. (A)]"

The DNS domain "bastion-shared-410.openshift.redhatworkshops.io" is not part of the domain of the cluster, it only happens to end with the same string value as the domain of the cluster.

The error appears to be at:

https://github.com/openshift/installer/blob/master/pkg/asset/installconfig/aws/validation.go#L463

    if !strings.HasSuffix(name, dottedClusterDomain) 

The definition of "dottedClusterDomain" is:

    dottedClusterDomain := ic.ClusterDomain() + "."

This causes the installer to misidentify this record as part of the DNS domain simply because it has the same suffix when it should be checking only if it has a "." then this suffix, something like:

    if !strings.HasSuffix("." + name, dottedClusterDomain) 


What did you expect to happen?

The installer should not consider this host to be part of the cluster domain.

How to reproduce it (as minimally and precisely as possible)?

Simply create a DNS record in the baseDomain with a name like "foo-<clusterName>".

Anything else we need to know?

https://github.com/openshift/installer/pull/5831